Transcript What neurodevelopmental disorders have been identified?

Psychology 304:
Brain and Behaviour
Lecture 23
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Development of the Nervous System and
Neurodevelopmental Disorders
1. Is the adult brain capable of change?
2. What neurodevelopmental disorders have been
identified?
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By the end of today’s class, you should be able to:
1. review evidence of neuroplasticity in adulthood.
2. describe the causes and symptoms of disorders
associated with neurodevelopmental abnormalities.
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Is the adult brain capable of change?
• Neuroplasticity was thought to be restricted to early
development. However, recent research has
demonstrated that mature brains are capable of
substantial reorganization.
• Among the research findings that have demonstrated the
neuroplasticity of the mature brain are two lines of
evidence:
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1. Neurogenesis in the adult brain
 A number of studies have demonstrated that new
neurons are constantly created in the olfactory bulb
and hippocampus.
 Exposure to enriched environments and regular
exercise contribute to neurogenesis in the adult brain.
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Neurogenesis in the Adult Brain
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2. Reoganization of the adult cortex
 Sensory and motor experiences in adulthood can lead
to reorganization of sensory and motor cortical maps
in the brain.
• The neuroplasticity of the mature brain suggests
promising treatments for degenerative brain diseases.
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What neurodevelopmental disorders have been
identified?
• The causes of neurodevelopmental disorders are
typically genetic, although some arise from prenatal
dietary deficiencies and neurotoxin exposure.
1. Anencephaly
 Occurs when the anterior neural tube does not
close, resulting in incomplete brain development.
Caused by genetic abnormalities, folic acid
deficiencies, and/or exposure to neurotoxins.
Anencephaly: Incomplete Brain Development
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Anencephaly: Incomplete Brain Development
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2. Spina bifida
 Occurs when the posterior neural tube does not
close, resulting in spinal cord defects and, in many
cases, paralysis of the lower limbs. Caused by
genetic abnormalities, folic acid deficiencies, and/or
exposure to neurotoxins.
 Four forms identified: occulta, meningocele,
meningomyelocele (cystica) and myeloschisis.
Spina Bifida: Four Forms
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Development of the Nervous System and
Neurodevelopmental Disorders
1. Is the adult brain capable of change?
2. What neurodevelopmental disorders have been
identified?
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